Details

One knew the electronic properties of the
nanotubes like their potential for the realization of a space elevator.
Researchers of Connecticut have just discovered their antimicrobial properties

. More than ever, the carbon nanotubes are presented in the form of one of the
major technological stakes of XXIieme century.
It is an unforeseen discovery which Menachem Elimelech, professor and flesh of
chemical and environmental engineering at the University of Yale, has just
carried out with his/her colleagues and which they analyze in an article of the
Langmuir newspaper of American Chemical
Society (ACS).
They were charged to study the possible toxicity of the carbon nanotubes in the
aquatic environments and more generally their possible impact on the food chain.
Indeed, the technology of the nanotubes doubtless will invade in the more or
less short term our world and in fact, the risks which they make weigh on the
environment and the life of every the day must carefully be evaluated. It is
necessary to know, for example, which with their shape of cylinder of the
thousands of times finer than a hair and especially their size, they can easily
be absorbed by a human cell.
The researchers concentrated initially on a particular class of nanotubes made
of only one layer of carbon atoms, Individual-walled the carbon nanotubes (SWCNTs).

A simple test was carried out. The researchers locked up bacteria known well,
the E. coil, in an incubator with of SWCNTs and this during approximately one
hour. With their surprise, the bacteria were killed but only in the case of a
direct contact with the nanotubes, which makes think of the researchers that the
damage caused by perforation of the membranes by the nanotubes which responsible
for died for E.coli. In
order to eliminate the possibility of a toxic action from metals present in the
nanotubes, one took care well, during their synthesis, to obtain particularly
pure products.
Currently, the team of professor Menachem Elimelech extends her research to
other types of nanotubes, and especially, with other bacteria in order to more,
in particular on the exact mechanism responsible for this bactericidal effect.
The applications could be important, not only to carry out implants delivering
of the drugs on the long term, but especially within the framework of research
on new antibiotics, whereas the number of those currently available does not
cease decreasing because of the increased resistance of the pathogenic germs.

In The Images:
MENACHEM ELIMELECH & In top, observations under the electron microscope of E.coli without SWCNTs in an incubator at the end of one hour, bellow the same experiment but with of SWCNTs. The number of micro-organisms strongly fell (Credit: Menachem Elimelech).